From owner-freebsd-hackers Thu Dec 21 12:16:36 2000 From owner-freebsd-hackers@FreeBSD.ORG Thu Dec 21 12:16:32 2000 Return-Path: Delivered-To: freebsd-hackers@freebsd.org Received: from netau1.alcanet.com.au (ntp.alcanet.com.au [203.62.196.27]) by hub.freebsd.org (Postfix) with ESMTP id 5538137B400 for ; Thu, 21 Dec 2000 12:16:31 -0800 (PST) Received: from mfg1.cim.alcatel.com.au (mfg1.cim.alcatel.com.au [139.188.23.1]) by netau1.alcanet.com.au (8.9.3 (PHNE_18979)/8.9.3) with ESMTP id HAA04997; Fri, 22 Dec 2000 07:15:48 +1100 (EDT) Received: from gsmx07.alcatel.com.au by cim.alcatel.com.au (PMDF V5.2-32 #37641) with ESMTP id <01JXZVUGQ4VKEMWOQE@cim.alcatel.com.au>; Fri, 22 Dec 2000 07:15:54 +1100 Received: (from jeremyp@localhost) by gsmx07.alcatel.com.au (8.11.0/8.11.0) id eBLKFj076929; Fri, 22 Dec 2000 07:15:45 +1100 (EST envelope-from jeremyp) Content-return: prohibited Date: Fri, 22 Dec 2000 07:15:45 +1100 From: Peter Jeremy Subject: Re: LINT vs. ipcs In-reply-to: ; from owner-freebsd-hackers-digest@FreeBSD.ORG on Thu, Dec 21, 2000 at 10:23:34AM -0800 To: float@firedrake.org Cc: freebsd-hackers@FreeBSD.ORG Message-id: <20001222071545.V54775@gsmx07.alcatel.com.au> MIME-version: 1.0 Content-type: text/plain; charset=us-ascii Content-disposition: inline User-Agent: Mutt/1.2.5i References: Sender: jeremyp@gsmx07.alcatel.com.au Sender: owner-freebsd-hackers@FreeBSD.ORG Precedence: bulk X-Loop: FreeBSD.ORG On Wed, 20 Dec 2000 20:05:58 +0000, void wrote" >LINT and the ipcs command seem to disagree on some points, like the >meaning of shmall (bytes vs. pages). In all such cases, the source code is the ultimate reference. > options SHMALL=1025 # max amount of shared memory (bytes) > vs. > shmall: 1024 (max amount of shared memory in pages) SHMALL is in pages. The comment in LINT is incorrect (this has been corrected in -CURRENT). >Also, some values are very different: I'm not sure that the values in LINT are supposed to reflect the default values in the system. ipcs will report the actual values. The default values can be found in /sys/kern/sysv_{shm,sem}.c >What I really want to know is, what do all these LINT variables mean? There is not a great deal of documentation about them in FreeBSD - only 1-line descriptions in and , as well as the source code mentioned above. In some cases, the explanations have been expanded in NOTES (the replacement for LINT) in -CURRENT. I've expanded the semop(2) and semctl(2) man pages in kern/12014. If you have access to other systems, try the Intro(2) man page on any System V OS (eg Solaris). > I have a user who needs more semaphores and shm segments >configured, and I want to make sure I tune the right ones. SysV semaphores are allocated in groups, where each group can contain multiple semaphores. SEMMNI defines the (system wide) number of semaphore groups and SEMMNS defines the (system wide) total number of semaphores in all groups. SEMMSL is a per-uid limit on the number of semaphores. SHMMNI defines the system-wide limit on shm segments and SHMSEG defines the per-process limit on shm segments. Peter To Unsubscribe: send mail to majordomo@FreeBSD.org with "unsubscribe freebsd-hackers" in the body of the message